Looks like they are trying to do a reverse resolve on ccsi.com and superkill.ccsi.com is refusing connection. Looks like something ccsi.com's spamkiller is doing. Winship wrote: > I run several library related professional discussion lists. I have > around 100 subscribers at the U.S. Library of Congress. Since a few weeks > ago, LC (loc.gov) has been rejecting all of my private mail from > [log in to unmask] to my subscribers who have written me about list problems. > I cannot even contact the listowner of several lists at loc.gov, even > though he thought that he was exempt from all filtering (i.e. blacklist/ > whitelist, etc.); he now knows different. He also doesn't know what the > problem is, but thinks it is blacklisting (I don't think he runs the > email system at LC). > > Could someone take a look at the error message below and give advice as > to what the problem is, and what might need to be done to correct it? > I haven't tried [log in to unmask] yet as my experience with "postmaster" > addresses is that if the item doesn't bounce (no such address) whatever > I send is studiously ignored, never a reply (wasn't like that 15 years > ago, but ....). > > I have this problem only with loc.gov, so far. I can send to anyone at > LC from my accounts at the U. at Buffalo, but that's a workaround, I need > to be able to send from ccsi.com. Any advice appreciated. > > Douglas Winship [log in to unmask] > > > ---------- Forwarded message ---------- > Date: Thu, 29 Dec 2005 14:43:01 -0600 (CST) > From: Mail Delivery Subsystem <MAILER-DAEMON> > To: [log in to unmask] > Subject: Returned mail: see transcript for details > > The original message was received at Wed, 28 Dec 2005 14:38:06 -0600 (CST) > from infinity.ccsi.com [216.236.168.2] (may be forged) > > ----- The following addresses had permanent fatal errors ----- > <[log in to unmask]> > (reason: 451 4.1.8 Domain of sender address [log in to unmask] does not > resolve) > > ----- Transcript of session follows ----- > ... while talking to sun8.loc.gov.: > >>>>DATA > > <<< 451 4.1.8 Domain of sender address [log in to unmask] does not resolve > <[log in to unmask]>... Deferred: 451 4.1.8 Domain of sender address > [log in to unmask] does not resolve > <<< 503 5.0.0 Need RCPT (recipient) > Message could not be delivered for 1 day > Message will be deleted from queue > > >